ladybird/AK/Tests/TestHashFunctions.cpp
Lenny Maiorani 18a40587ea HashFunctions: constexpr capability
Problem:
- Hash functions can be `constexpr`, but are not.

Solution:
- Change `inline` keyword to `constexpr`.
- Add `static_assert` tests to ensure the hash functions work in a
  `constexpr` context.
2020-10-21 19:42:12 +02:00

83 lines
2.9 KiB
C++

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#include <AK/TestSuite.h>
#include <AK/HashFunctions.h>
#include <AK/Types.h>
TEST_CASE(int_hash)
{
static_assert(int_hash(42) == 3564735745u);
static_assert(int_hash(0) == 1177991625u);
}
TEST_CASE(double_hash)
{
static_assert(double_hash(42) == 524450u);
static_assert(double_hash(0) == 12384u);
}
TEST_CASE(pair_int_hash)
{
static_assert(pair_int_hash(42, 17) == 339337046u);
static_assert(pair_int_hash(0, 0) == 954888656u);
}
TEST_CASE(u64_hash)
{
static_assert(u64_hash(42) == 2824066580u);
static_assert(u64_hash(0) == 954888656u);
}
TEST_CASE(ptr_hash)
{
// These tests are not static_asserts because the values are
// different and the goal is to bind the behavior.
if constexpr (sizeof(FlatPtr) == 8) {
EXPECT_EQ(ptr_hash(FlatPtr(42)), 2824066580u);
EXPECT_EQ(ptr_hash(FlatPtr(0)), 954888656u);
EXPECT_EQ(ptr_hash(reinterpret_cast<const void*>(42)), 2824066580u);
EXPECT_EQ(ptr_hash(reinterpret_cast<const void*>(0)), 954888656u);
} else {
EXPECT_EQ(ptr_hash(FlatPtr(42)), 3564735745u);
EXPECT_EQ(ptr_hash(FlatPtr(0)), 1177991625u);
EXPECT_EQ(ptr_hash(reinterpret_cast<const void*>(42)), 3564735745u);
EXPECT_EQ(ptr_hash(reinterpret_cast<const void*>(0)), 1177991625u);
}
}
TEST_CASE(constexpr_ptr_hash)
{
// This test does not check the result because the goal is just to
// ensure the function can be executed in a constexpr context. The
// "ptr_hash" test binds the result.
static_assert(ptr_hash(FlatPtr(42)));
}
TEST_MAIN(HashFunctions)